Jennifer has oversight responsibility for the servicing and repair of her company's fleet of cars, so she frequently calls the garage mechanic to inquire whether service on various cars has been completed. because service completion times are unpredictable, she is likely to be reinforced with positive responses to her inquiries on a schedule.

variable-interval

Explanation:

In a variable-interval schedule, reinforcement is presented if the body emits at least one response after a variable interval of time. Generally, this scheme is represented by putting the average time of the variable interval. For example: VI-10min means that the booster is displayed after an average of 10 minutes and only for the first response issued.

The variable-interval schedule results in a high frequency of responses.

As Jennifer's company car repair and maintenance service completion times are unpredictable, it will likely be reinforced with positive answers to your questions. This is an example of variable-interval schedule.

according to hess's theory, when the magma cooled, it would expand and push the tectonic plates apart. it would push the north and south america plates to the west and eurasia and africa ones to the east. the atlantic ocean would get wider but the coastlines of the masses would stay the same.

harry hammond hess was a geologist and a united states navy officer in the second world war. he is considered to be one of the founding fathers of the theory of plate tectonics. he is known for his theories on sea floor spreading, stating that the movement of the continents was the result of see floor spreading. the continents are attached to the plates and do not move separately. the plates themselves shift and change shape, carrying the continents along.